 /*******************************************************************************
  * Copyright (c) 2000, 2006 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/

 package org.eclipse.ui;

 import org.eclipse.core.runtime.IProgressMonitor;

 /**
  * Workbench parts implement or adapt to this interface to participate
  * in the enablement and execution of the <code>Save</code> and
  * <code>Save As</code> actions.
  *
  * @since 2.1
  * @see org.eclipse.ui.IEditorPart
  */
 public interface ISaveablePart {

     /**
      * The property id for <code>isDirty</code>.
      */
     public static final int PROP_DIRTY = IWorkbenchPartConstants.PROP_DIRTY;

     /**
      * Saves the contents of this part.
      * <p>
      * If the save is successful, the part should fire a property changed event
      * reflecting the new dirty state (<code>PROP_DIRTY</code> property).
      * </p>
      * <p>
      * If the save is cancelled through user action, or for any other reason, the
      * part should invoke <code>setCancelled</code> on the <code>IProgressMonitor</code>
      * to inform the caller.
      * </p>
      * <p>
      * This method is long-running; progress and cancellation are provided
      * by the given progress monitor.
      * </p>
      *
      * @param monitor the progress monitor
      */
     public void doSave(IProgressMonitor monitor);

     /**
      * Saves the contents of this part to another object.
      * <p>
      * Implementors are expected to open a "Save As" dialog where the user will
      * be able to select a new name for the contents. After the selection is made,
      * the contents should be saved to that new name. During this operation a
      * <code>IProgressMonitor</code> should be used to indicate progress.
      * </p>
      * <p>
      * If the save is successful, the part fires a property changed event
      * reflecting the new dirty state (<code>PROP_DIRTY</code> property).
      * </p>
      */
     public void doSaveAs();

     /**
      * Returns whether the contents of this part have changed since the last save
      * operation. If this value changes the part must fire a property listener
      * event with <code>PROP_DIRTY</code>.
      * <p>
      * <b>Note:</b> this method is called often on a part open or part
      * activation switch, for example by actions to determine their
      * enabled status.
      * </p>
      *
      * @return <code>true</code> if the contents have been modified and need
      * saving, and <code>false</code> if they have not changed since the last
      * save
      */
     public boolean isDirty();

     /**
      * Returns whether the "Save As" operation is supported by this part.
      *
      * @return <code>true</code> if "Save As" is supported, and <code>false</code>
      * if not supported
      */
     public boolean isSaveAsAllowed();

     /**
      * Returns whether the contents of this part should be saved when the part
      * is closed.
      *
      * @return <code>true</code> if the contents of the part should be saved on
      * close, and <code>false</code> if the contents are expendable
      */
     public boolean isSaveOnCloseNeeded();
 }

